The ferrite cores are from http://www.mag-inc.com/ and are the largest they
manufacture!!

Ferrite Pwer transformer -- the duct tape is temporary :p
Specs: 4 primary turns (300A)
30 secondary turns (100A)
The primary is 4 turns of copper strap.. it is slightly smaller than the width
of the tranformer window.
Terminations to the strap were made with some rectangualr copper wire, two pieces
for each side.
I used special motor rewinding insulation between turns.. this stuff is very
tough.

The strap is actually two pieces of copper flashing plate, the termination
wires are sandwitched inbetween these two plates and then soldered.

Here is a top view, isnt it beautiful ? I used a piece of hard wood as the
former..

Top view with 30 turns of secondary winding now on it. The secondary is centertapped.

Completed transformer ! I made the stainless steel core clamp.. I didnt have
any stainless bolts long enough so I welded some bar in to extend them.